Adaptable Audio Devices and Systems

1. A sound-producing device, comprising: a housing; an audio transducer disposed within the housing; a digital controller and a signal processor disposed within the housing, the signal processor coupled to the digital controller and having an analog input, a digital input, and an audio output, the audio output coupled to the audio transducer; an audio jack suitable for removable connection to an audio plug, the audio jack disposed proximate an exterior of the housing and comprising two conductive contacts to receive an audio signal; and a switch disposed within the housing, the switch comprising a switch input, a first switch output, and a second switch output, the switch input coupled to the audio jack to receive the audio signal from the two conductive contacts, the first switch output coupled to the digital input of the signal processor through the digital controller, and the second switch output coupled to the analog input of the signal processor but bypassing the digital controller; wherein, in a first switch state, the switch connects the switch input to the first switch output but not to the second switch output, and in a second switch state, the switch connects the switch input to the second switch output but not to the first switch output.

2. The device of claim 1 , wherein the switch shifts from the first switch state to the second switch state in response to a control signal from the digital controller.

3. The device of claim 1 , wherein the switch input couples to the two conductive contacts of the audio jack by a second switch, the device further comprising: a receiving device disposed in the housing, the receiving device configured to receive audio information wirelessly from a radio frequency source exterior to the housing, the receiving device having a second audio output, the second audio output also coupling to the switch input through the second switch.

4. The sound-producing device of claim 1 , further comprising: a power source configured to provide electrical power to the audio jack.

5. A system, comprising: the sound-producing device of claim 4 ; and an external interface comprising signal conversion circuitry and an audio plug, the signal conversion circuitry adapted to convert a first audio-encoded signal to a conditioned audio-encoded signal, the conditioned audio-encoded signal being compatible with the sound-producing device but the first audio-encoded signal not being compatible with the sound-producing device, the audio plug adapted to mate with the audio jack; wherein the power source in the sound-producing device powers the signal conversion circuitry in the external interface through the audio plug and the audio jack; and wherein the external interface provides the conditioned audio-encoded signal to the two conductive contacts of the audio jack through the audio plug.

6. The device of claim 4 , wherein the power source is disposed in the housing and provides electrical power needed to operate substantially all electrical components of the sound-producing device.

7. The device of claim 4 , wherein the power source comprises a rechargeable battery.

8. The device of claim 1 , wherein the device is a loudspeaker.

9. The device of claim 1 , wherein the device is a headphone set.

10. The device of claim 1 , further comprising: a user interface mounted to the housing and coupled to the digital controller, the user interface adapted to provide status information to the digital controller, or adapted to receive status information from the digital controller, or both.

11. A sound-producing device, comprising: a housing within which is disposed an audio transducer, a digital controller, a signal processor, and a switch; and an audio jack mounted to the housing and adapted to mate with an audio plug to receive therefrom an audio signal; wherein the signal processor has an analog input, a digital input, and an audio output, the audio output coupled to the audio transducer; wherein the switch includes a switch input, a first switch output, and a second switch output, the switch input coupled to receive the audio signal from the audio jack, the first switch output coupled to the digital input of the signal processor, and the second switch output coupled to the analog input of the signal processor; and wherein the switch selectively connects the switch input to the first switch output but not to the second switch output in a first switch state, and the switch selectively connects the switch input to the second switch output but not to the first switch output in a second switch state.

12. The device of claim 11 , wherein the switch shills from the first switch state to the second switch state in response to a control signal from the digital controller.

13. The device of claim 11 , wherein the switch input couples to the audio jack by a second switch, the device further comprising: a receiving device disposed in the housing, the receiving device configured to receive audio information wirelessly from a radio frequency source exterior to the housing, the receiving device having a second audio output, the second audio output also coupling to the switch input through the second switch.

14. The device of claim 11 , further comprising: a power source configured to provide electrical power to the audio jack.

15. A system, comprising: the device of claim 14 ; and an external interface comprising signal conversion circuitry and an audio plug, the signal conversion circuitry adapted to convert a first audio-encoded signal to a conditioned audio-encoded signal, the conditioned audio-encoded signal being compatible with the sound-producing device but the first audio-encoded signal not being compatible with the sound-producing device, the audio plug adapted to mate with the audio jack; wherein the power source in the sound-producing device powers the signal conversion circuitry in the external interface through the audio plug and the audio jack; and wherein the external interface provides the conditioned audio-encoded signal to the audio jack through the audio plug.

16. The device of claim 14 , wherein the power source is disposed in the housing and provides electrical power needed to operate substantially all electrical components of the sound-producing device.

17. The device of claim 14 , wherein the power source comprises a rechargeable battery.

18. The device of claim 11 , wherein the device is a loudspeaker.

19. The device of claim 11 , wherein the device is a headphone set.

20. The device of claim 11 , further comprising: a user interface mounted to the housing and coupled to the digital controller, the user interface adapted to provide status information to the digital controller, or adapted to receive status information from the digital controller, or both.